Mechanical properties of waste paper/jute fabric reinforced polyester resin matrix hybrid composites

Jute fibre reinforced biodegradable composites using starch as a biological macromolecule: Fabrication and performance evaluation

The aim of this study is to develop environment friendly packaging and life style materials for replacing conventionally explored hazardous synthetic materials. The study carried out by using raw jute fibre reinforced thermoplastic corn starch (TPCS) is to develop biodegradable flexible composite materials. Flexible composites are prepared by maintaining with different fibre content (30 %, 40 % and 50 wt%). A thin coating of polyurethane based formulation is applied on one side of the developed composite to make it water resistant. Composite samples are examined in terms of their tensile properties, tear resistance, folding endurance, water absorbency, capillary action etc. The results show that flexible composites, having 50 % fibre content have tensile strength of 12.8 MPa and 12 MPa at cross and machine direction respectively compared to 3.1 MPa for the TPCS film. The Water drop test on the coated side of the developed material concluded that there is no water penetration even after 60 min of wetting. The interaction between two hydrophilic components is established with FTIR analysis. The XRD analysis was carried out to find the crystallinity of TPCS, Jute fibre and composite samples. Surface morphology and fibre/matrix interaction is observed by SEM. The detail chemical mechanism involved of fibre matrix interaction also been postulated. The scientific finding shows that the developed flexible material can be suitable for making packaging and life style items.

A Review on Bast-Fibre-Reinforced Hybrid Composites and Their Applications

The development of eco-friendly products to protect the environment has become a topical subject in the research and industrial communities. This is a result of strict environmental regulations necessitating the development of novel strategies to reduce our reliance on petroleum-based products, which exert a negative effect on our ecosystem. Bast-fibre-based hybrids have been extensively studied for various applications due to their eco-friendliness and cost effectiveness. There is a very limited number of review articles covering the properties and preparation of bast-fibre-based hybrid composites. This review is designed to provide an overview of the preparation and application of bast-fibre-based hybrid composites. It covers the thermal properties, mechanical properties, moisture absorption and flame-retardant properties of bast hybrid composites. This review not only summarises recent advances on the use and preparation of bast hybrid composites, it also presents a future outlook.

Waste Paper as a Valuable Resource: An Overview of Recent Trends in the Polymeric Composites Field

This review focuses on polymeric waste-paper composites, including state-of-the-art analysis with quantitative and qualitative discussions. Waste paper is a valuable cellulose-rich material, produced mainly from office paper, newspaper, and paper sludge, which can be recycled and returned to paper production or used in a new life cycle. A systematic literature review found 75 publications on this material over the last 27 years, with half of those published during the last five years. These data represent an increasing trend in the number of publications and citations that have shown an interest in this field. Most of them investigated the physicomechanical properties of composites using different contents of raw waste paper or the treated, modified, and cellulose-extracted types. The results show that polyethylene and polypropylene are the most used matrices, but polylactic acid, a biodegradable/sourced polymer, has the most citations. The scientific relevance of waste-paper composites as a subject includes the increasing trend of the number of publications and citations over the years, as well as the gaps identified by keyword mapping and the qualitative discussion of the papers. Therefore, biopolymers and biobased polymers could be investigated more, as well as novel applications. The environmental impact in terms of stability and degradation should also receive more attention regarding sustainability and life cycle analyses.

Experimental Investigation on the Mechanical and Physical Properties of Glass/Jute Hybrid Laminates

Natural fibres have been partly substituting synthetic fibres in polymer composites due to their renewable character and many other advantages, and sometimes, they can be hybridized into a single composite for a better combination of properties. This work aims to study the effect of hybridization and stacking sequence on the mechanical and physical properties of the glass/jute laminates. For that, pure jute, pure glass and glass/jute hybrids were manufactured by vacuum infusion process using orthophthalic polyester resin. The composites were characterized via C-scan analysis, density, volume fraction of constituents and optical microscopy analyses. Mechanical properties were obtained from tensile, compression and shear tests. The longitudinal properties were higher than transverse properties for all laminates. The hybrids presented intermediate density and mechanical properties compared to pure glass and pure jute laminates. The hybrids produced similar density and tensile modulus, but with small differences in tensile strength and compressive strength which were justified based on variations in resin and void content due to the influence of the stacking sequence (glass/jute interlayer regions). In addition, the pure glass and the hybrid laminates displayed acceptable failure morphology in the in-plane shear test, but not the pure jute laminate.

A Review on the Effect of Fabric Reinforcement on Strength Enhancement of Natural Fiber Composites

The main objective of this study is to examine the impact of reinforcements on the strength of natural fiber composites. Recent advancements in natural fiber composites have minimized the usage of man-made fibers, especially in the field of structural applications such as aircraft stiffeners and rotor blades. However, large variations in the strength and modulus of natural fiber degrade the properties of the composites and lower the safety level of the structures under dynamic load. Without compromising the safety of the composite structure, it is significant to enrich the strength and modulus of natural fiber reinforcement for real-time applications. The strength and durability of natural fiber can be enriched by reinforcing natural fiber. The reinforcement effect on natural fiber in their woven, braided, and knit forms enhances their structural properties. It improves the properties of natural fiber composites related to reinforcement with short and random-orientation fibers. The article also reviews the effect of the hybridization of natural fiber with cellulosic fiber, synthetic fiber, and intra-ply hybridization on its mechanical properties, dynamic mechanical properties, and free vibration characteristics, which are important for predicting the life and performance of natural fiber composites for weight-sensitive applications under dynamic load.

Recycling of 100% Cotton Fabric Waste to Produce Unsaturated Polyester-Based Composite for False Ceiling Board Application

In recent years, the garment and textile industries generate millions of tons of textile waste every year around the world. Textile wastes are one of the disposed of materials and the sum of disposed of material squander materials expanded from year to year. For this reason, regenerating and utilizing the textile waste item as resources and decreasing environmental pollution may be an extraordinary opportunity. This research is aimed at manufacturing unsaturated polyester composite reinforced with 100% cotton fabric waste for ceiling board application using a manual mixing process followed by the compression molding method. The statistical results showed that mechanical properties of the produced composite samples such as tensile, compressive, flexural, and impact strength are affected by fiber mixed ratio and matrix loading at $\alpha =0.05$ . The composite ceiling reinforced with 33 weight % cotton fabric waste and a matrix of 67 weight % unsaturated polyester had a maximum tensile strength of 198 MPa, the flexural strength of 30.1 MPa, and compressive strength of 1105.3 MPa. On the contrary, the false ceiling board made from 10% cotton fabric waste and matrix of 90% unsaturated polyester had a lower tensile strength of 112.6 MPa, flexural strength of 21.5 MPa, and compressive strength of 867.5 MPa. Generally, the manufactured composites’ mechanical behaviors were comparable to existing commercial ceiling boards and the output of this research work can protect the environmental pollution by reducing textile waste disposed to landfills.

Electrospray Deposition of Cellulose Nanofibers on Paper: Overcoming the Limitations of Conventional Coating

While the potential of cellulose nanofibers to enhance the mechanical and barrier properties of paper is well-known, there are many uncertainties with respect to how to apply them. In this study, we use not only bulk addition of micro-/nanofibers and bar coating with oxidized nanofibers, but also a combination of these and, as a novel element, electrospray deposition of nanofiber dispersions. Characterization involved testing the strength of uncoated and coated paper sheets, their resistance to air flow, their Bendtsen roughness, and their apparent density, plus visualization of their surface and cross-sections by scanning electron microscopy. As expected, bulk addition to the unrefined pulp was sufficient to attain substantial strengthening, but this enhancement was limited to approximately 124%. Following this, surface addition by bar coating improved air resistance, but not strength, since, as applying nanocellulose at high consistency was technically unfeasible, this was performed several times with detrimental drying stages in between. However, replacing bar coating with electrospraying helped us overcome these apparent limitations, producing enhancements in both barrier and tensile properties. It is concluded that electrosprayed nanofibers, owing to their uniform deposition and favorable interactions, operate as an effective binder between fibers (and/or fines).

Low-Cost Inkjet-Printed Temperature Sensors on Paper Substrate for the Integration into Natural Fiber-Reinforced Lightweight Components

In a unique approach to develop a “green” solution for in-situ monitoring, low-cost inkjet-printed temperature sensors on paper substrate were fully integrated into natural fiber-reinforced lightweight components for which structural health monitoring is becoming increasingly important. The results showed that the sensors remained functional after the vacuum infusion process; furthermore, the integration of the sensors improved the mechanical integrity and stability of the lightweight parts, as demonstrated by tensile testing. To verify the qualification of the printed sensors for the target application, the samples were exposed to varying temperature and humidity conditions inside of a climate chamber. The sensors showed linear temperature dependence in the temperature range of interest (−20 to 60 °C) with a TCR ranging from 1.576 × 10−3 K−1 to 1.713 × 10−3 K−1. Furthermore, the results from the tests in humid environments indicated that the used paper-based sensors could be made almost insensitive to changes in ambient humidity by embedding them into fiber-reinforced lightweight materials. This study demonstrates the feasibility of fully integrating paper-based printed sensors into lightweight components, which paves the way towards integration of other highly relevant sensing devices, such as strain and humidity sensors, for structural health monitoring of smart, sustainable, and environmentally compatible lightweight composite materials.

Enhancement of Interface between Lignocellulosic Fibers and Polypropylene Matrix via the Structure Alteration of Lignin at Elevated Temperatures

This paper investigated the feasibility of enhancing the interface between lignocellulosic fibers and a polypropylene matrix via structure alteration of lignin at elevated temperatures. Alkali treatment can remove gum substances from lignocellulose fibers effectively at elevated temperatures but easily causes damages to fiber strength. In previous studies on directional delignification of lignocellulosic fibers, loss of fiber strength is avoided but condensation and degradation of lignin are accelerated. So far, few reports have been available on the effect of lignin structures on the interface between fibers and a matrix. In this study, jute fibers with different lignin structures are produced at 100 and 130 °C for reinforcing a polypropylene matrix. The interface between the fibers and matrix is analyzed. The result shows that decrease in aliphatic hydroxyl concentration by 9.5% at 130 °C from 3 to 5 h contributes to a 14.2% decrease in the surface energy of jute fibers. Meanwhile, the polydispersity index of lignin decreases from 1.21 to 1.15. Centralized distribution of lignin molecule-weight and reduction in fiber surface energy improves the interface between the fibers and matrix, which manifests as a 30.8% increase in the impact strength of the composites. Similar improvement is not observed in the composites reinforced with jute fibers at 100 °C, due to the absence of lignin-structure changes. This paper provides a new strategy to improve the interface between lignocellulose fibers and a hydrophobic matrix.

Influence of Gamma Radiation on Mechanical Properties of Jute Fabric-Reinforced Polymer Composites

Woven jute fabric was used as a reinforcing material for making two types of composite, named Jute/PR and Jute/Epoxy, with two different matrixes of polyester resin and epoxy, respectively, by hand layup techniques. Five different doses of gamma radiation from 100 to 500 krad were used to investigate the effects of the mechanical properties of the composites and the jute fabrics. Though gamma radiation improved the mechanical properties, such as the tensile strength (TS) and Young’s modulus (Y), and decreased the elongation at break % (Eb%) of the composites, it deteriorated all these properties for jute fabrics. The highest values of TS and Y and the lowest value of Eb% were found to be 39.44 Mpa, 1218.33 Mpa, and 7.68% for the Jute/PR; and 48.83 Mpa, 1459.67 Mpa, and 3.68% for the Jute/Epoxy composites, respectively, at a 300 krad gamma radiation dose. A further increase in dose altered all these properties; thus, 300 krad was found to be the optimum dose for both of the composites. Between the two composites, gamma radiation influenced the Jute/PR composite more than the Jute/Epoxy composite.

Characterization of Hybrid Oil Palm Empty Fruit Bunch/Woven Kenaf Fabric-Reinforced Epoxy Composites

In this research, the physical, mechanical and morphological properties of oil palm empty fruit bunch (EFB) mat/woven kenaf fabric-reinforced epoxy composites have been investigated. The oil palm EFB/woven kenaf fabrics were varied, with weight ratios of 50/0 (T1), 35/15 (T2), 25/25 (T3), 15/35 (T4) and 0/50 (T5). The composites were fabricated using a simple hand lay-up technique followed by hot pressing. The result obtained shows that an increase in kenaf fiber content exhibited higher tensile and flexural properties. On the other hand, the opposite trend was observed in the impact strength of hybrid composites, where an increase in kenaf fiber content reduced the impact strength. This can be corroborated with the physical properties analysis, where a higher void content, water absorption and thickness swelling were observed for pure oil palm EFB (T1) composites compared to other samples. The scanning electron microscopy analysis results clearly show the different failure modes of the tensile fractured samples. Statistical analysis was performed using one-way ANOVA and shows significant differences between the obtained results.

A green approach of improving interface and performance of plant fibre composites using microcrystalline cellulose

In contrast to the conventional methods of improving interface and performances of plant fibre composites through fibre surface modification, this paper reports a novel approach based on the dispersion of microcrystalline cellulose (MCC) in the composite's matrix. MCC was dispersed within the matrix of jute fibre reinforced epoxy composites to improve the fibre/matrix interface as well as mechanical, dynamic-mechanical and thermal performances. To develop these novel jute/epoxy/MCC hierarchical composites, MCC was first dispersed within an epoxy resin using a short ultrasonication process (1 h) and subsequently, the MCC/epoxy suspensions were infused through jute fabrics using the vacuum infusion technique and cured. Hierarchical composites by dispersing multi-walled carbon nanotubes (MWCNTs) within the epoxy resin were also fabricated to compare their performance with MCC based hierarchical composites. Interface (single fibre pull-out test), mechanical (tensile, flexural, izod impact), thermal (thermogravimetric analysis) and dynamic mechanical performances of the developed composites were thoroughly studied. It was observed that the addition of MCC to the epoxy matrix led to a significant increase in the interfacial shear strength (IFSS) between jute fibres and the epoxy matrix and consequently, resulted up to 18.4%, 21.5%, 28.3%, 67% and 49.5% improvements in the tensile strength, flexural strength, impact energy, storage and loss moduli, respectively as compared to the neat jute/epoxy composites. The above improvements achieved with MCC were significantly higher as compared to the MWCNT based hierarchical composites developed using the same technique.

Numerical study on rupture process of fiber-reinforced composites

INTRODUCTION

This study aims to investigate the strength characteristics of fiber composites under uniaxial tensile stress.

METHODS

A tensile failure finite element model based on fracture mechanics was built for fiber composites. The principal stress concentration-release-transfer evolution and the crack propagation of the composites under the conditions of equal single fiber width, unequal quantity, and equal total fiber width and unequal quantity were discussed.

RESULTS

The tensile strength of the composites increased with fiber quantity when the width of each single fiber was equal.

CONCLUSIONS

The tensile strength of the composites increased with fiber quantity when the total width of the composite fiber was equal.

Searching for Natural Conductive Fibrous Structures via a Green Sustainable Approach Based on Jute Fibers and Silver Nanoparticles

This paper provides new insights regarding jute fibers functionalization with silver nanoparticles (Ag NPs) with improved conductivity values and highlights the sustainability of the processes involved. These NPs were applied onto jute fabrics by two different sustainable methods: ultraviolet (UV) photoreduction and by using polyethylene glycol (PEG) as a reducing agent and stabilizer. Field Emission Scanning Electron Microscopy (FESEM) images demonstrated that the Ag NPs were incorporated on the jute fibers surface by the two different approaches, with sizes ranging from 70 to 100 nm. Diffuse reflectance spectra revealed the plasmon absorption band, corresponding to the formation of metallic Ag NPs, in all samples under study. Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR) was used to characterize the obtained samples, demonstrating NPs adsorption to the surface of the fibers. The resistivity value obtained by the two-point probe method of the jute fabric without functionalization is about 1.5 × 10⁷ Ω·m, whereas, after NPs functionalization, it decreased almost 15,000 times, reaching a value of 1.0 × 10³ Ω·m. Further research work is being undertaken for improving these values, however, 1000 Ω·m of resistivity (conductivity = 0.001 S/m) is already a very reasonable value when compared with those obtained with other developed systems based on natural fibers. In summary, this work shows that the use of very simple methodologies enabled the functionalization of jute fibers with reasonable values of conductivity. This achievement has a huge potential for use in smart textile composites.